>

>ruta='server\megasystem\reports\'
>
>lnfilecount = adir(lafiles,ruta+"*.frx")
>
>

>
>in server\megasystem \ reports I have 300 files but returns lnfilecount =0

It should be either

ruta = "\\server\megasystem\reports\"

or

ruta = "c:\server\megasystem\reports\"

In other words, your directory should be either UNC path or normal path with a drive name in front.